CRP and infection: Taking SMPP as the dependent variable (assignment: NSMPP = 0, SMPP = 1) and taking the significant and infection-related indicators in the univariate analysis as independent variables for multivariate logistic regression analysis, the results showed that the left upper lobe CT score (odds ratio [OR] = 0.499, 95% confidence interval [CI]: 0.28–0.892), SOFA score (OR = 1.913, 95% CI: 1.295–2.826), APACHE II score (OR = 2.641, 95% CI: 1.812–3.848), BS score (OR = 1.833, 95% CI: 1.248–2.692), and CRP (OR = 0.98, 95% CI: 0.963–0.997) were independent risk factors for SMPP (P < 0.05) (see Table 3).